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Scientific name: Asclepias syriaca

Common milkweed is a native perennial which commonly occurs in fields, open woods and roadsides. It can grow to 3-4 feet tall but there are other species that are more compact and work well in gardens.

Milkweed got its name from the milk-like sap that runs from its cut stems.

To learn more, watch this video.


Stout, upright stems with thick, broad oblong leaves, which can be up to 8 inches long in a mature plant.


Domed, slightly drooping clusters of fragrant, pinkish-purple flowers appear mostly on top of the stalks.  Flowers give way to seed pods (2-4 inches long). When they split open in the late summer or early fall, the wind will carry their seeds.

Blooming Season

Late spring into summer.

What You Can Do

Plant a few milkweeds in your garden (more than one, as there needs to be enough food for the hungry caterpillar) and see the butterflies flock to you!

If you are looking for a compact milkweed that looks good and flowers for a long period of time,  buy some Asclepias tuberosa, which is commonly called Butterfly Weed. It is equally popular with butterflies and other pollinators. It has long lasting orange flowers (see photo below from a local garden, complete with a monarch caterpillar!). It is also a native plant.


Milkweed is found in sunny meadows and roadsides. It does fine in poor soils if they are well-drained.

You can find milkweed in the meadow at Old Field Preserve. There are also many milkweed plants at Ward Pound Ridge reservation.

Similar Species

There are several types of milkweed besides the common. The swamp milkweed will grow in damp, heavy or wet soils as its name suggest. Butterfly Weed, the orange milkweed is fabulous for the home garden as it does not get too tall and flowers almost non-stop through the season.

Dogbane looks very similar and also has a milky sap, but it is not a food for monarch caterpillars.

Ecosystem Connections

Flowers are a nectar source for many butterflies and bees.

Most importantly, the monarch butterfly lays her eggs only on the Milkweed plant, as this is the only food the hatched caterpillars can eat.

Human Connections

This is an important plant for butterfly gardens or naturalized/native plant areas.

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